Green upcycling Pistachio shells into a high-performance functional biocomposite for hazardous dye removal from textile effluents

This is the authors' abstract. We don't add key points for this paper.

The increasing presence of dyes in wastewater has driven the development of efficient and cost-effective adsorbents. In response, a novel arginine-polyaniline@pistachio shell (Arg-PANI@PS) biocomposite was synthesized via in situ chemical polymerization. The synthesized adsorbent was thoroughly characterized using various techniques, including FTIR, SEM/EDS, XRD, TGA, and PZC analyses. The adsorption performance of the biocomposite for Orange G dye was systematically evaluated under different conditions, including Arg-PANI@PS dosage, temperature, initial OG concentration, solution pH, and contact time, achieving over 95% removal with 0.35 g/L of the biocomposite in 60 min. Thermodynamic parameters verified that the adsorption process was spontaneous and endothermic. The adsorption of OG onto Arg-PANI@PS followed pseudo-second-order kinetics and conformed to the Langmuir isotherm, exhibiting a high adsorption capacity of 130.73 mg/g. Additionally, the effect of coexisting interfering ions was assessed, further confirming the material's potential for selective adsorption in complex environments. Notably, Arg-PANI@PS maintained strong adsorption performance even after four regeneration cycles, highlighting its promising reusability as a biocomposite adsorbent.